66515490 has 24 divisors (see below), whose sum is σ = 172940508. Its totient is φ = 17737440.

The previous prime is 66515467. The next prime is 66515497. The reversal of 66515490 is 9451566.

66515490 is a `hidden beast` number, since 66 + 51 + 549 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 60419529 + 6095961 = 7773^2 + 2469^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (66515497) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 369441 + ... + 369620.

Almost surely, 2^66515490 is an apocalyptic number.

66515490 is an abundant number, since it is smaller than the sum of its proper divisors (106425018).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66515490 is a wasteful number, since it uses less digits than its factorization.

66515490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739074 (or 739071 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 66515490 is about 8155.7029126863. The cubic root of 66515490 is about 405.1734053964.

The spelling of 66515490 in words is "sixty-six million, five hundred fifteen thousand, four hundred ninety".